Electrode humidifier

ABSTRACT

An electrode humidifier has the key characteristic that its electrodes are continuously wiped during operation of the humidifier generating steam by wiper blades. The wiper blades may rotate continuously, mounted on a shaft, wiping electrodes in the form of circular discs so as to wipe the whole surfaces of the electrodes or the blades may reciprocate angularly wiping on the electrodes. A linear actuator for linear reciprocation may be used for a boiler bottle type of humidifier.

FIELD OF THE INVENTION

This invention lies in the field of electrode humidifiers or “electrode boilers”, at the heart of which is the “boiler”, “bottle” or “steam tank”, the purpose of which is to supply steam to a space and which find many applications. For example, application to computer rooms (to control static electricity build up), operating theatres, offices, shops, product processing plant, holding containers, storage facilities, and other environments and for humans where health considerations apply. The invention also applies to any other equipment where scale is deposited on a process surface, for example industrial electrode boilers.

BACKGROUND

Electrode humidifiers may be both single phase and three phase with electrodes immersed in water and generally operate by controlling the level of water into which electrodes are partially or fully immersed in order to control the rate of steam production. A problem inherent in humidifiers is scale build up and other deposits of solids due to the boiling away as steam and a purging cycle is commonly resorted to. Periodic shut down and scraping and cleaning off of scale is generally required despite purging. Attempts at solving these problems have included chemical treatment, e.g. to convert sodium chloride ions to sodium sulphate, magnetic treatments of the water and electronic pulsing at selected frequencies. However, all of these efforts have not fully solved the problems mentioned above with resulting cost and inefficiency consequences.

THE INVENTION

The present invention provides an electrode humidifier characterized in that the electrodes are engaged by wiper means and a relative motion between the electrodes and the wiper means is continuously or continually applied during operation of the humidifier. The continuous action continues without interruption and the continual action is very frequent without cessation.

With the electrodes stationary and the wiper means moved, this simplifies the electrical connections to the electrodes which are located in the steam tank in which water is contained for production of steam.

The wiper means may further operate on other scale collecting surfaces.

The wiper means, which may be in the form of blades, are preferably moved in a rotational movement, as this allows them to be mounted on a shaft which can easily be driven rotationally. The electrodes are preferably in a form of a circular disc so that the wiper blades move rotationally over the whole electrode surface with a suitable rotational speed.

If it is the electrodes that are moved, they would again preferably be in a form of circular discs with the stationary wiper blades acting against them. The wiper blades are fixed on an insulating mounting between the electrodes.

A preferred general construction of a humidifier according to this preferred embodiment of the invention is a rectangular tank with electrodes depending from the roof of the tank, a horizontal shaft extending across the tank and carrying wiper blades arranged to wipe the operative surfaces of the electrodes, the shaft passing through the tank wall at one end to be driven by a suitable means, for example a suitably geared electric motor. A side water inlet, upper steam outlet and a bottom drain are provided. Two, three or four electrodes are provided for single phase electrical supply and four electrodes for three phase supply. A humidifier made with provision of four electrodes can conveniently be powered as a single phase device or a three phase device by arranging the electrical connections to the electrodes accordingly. It is found convenient to make at least part of the tank with transparent walls and/or roof to allow observing the operation and the conditions in the humidifier, as an optional feature.

The relative motion between the electrodes and the wiper means may in accordance with an alternative embodiment of the invention be continuously applied during operation of the humidifier by a linear actuator means. The linear actuator means must preferably provide an axial movement that oscillates back and forth.

The embodiment of the invention that uses reciprocating linear movement allows application to a steamer bottle which has a generally hollow upright cylindrical shape with linear electrodes depending from the top of the bottle.

The water level may be controlled to rise no higher than just below the shaft in order to avoid scale and other deposits building up on the shaft, however, although this was adopted in a prototype it will not be followed in further models.

It is found that continuously wiping the electrode surfaces removes deposits before they become hardened and strongly attached to the electrode surfaces, as occurs with present humidifiers.

An inlet, outlet and a bottom water drain are provided. Means to prevent back siphoning are preferably added and are mandatory in some jurisdictions. Three electrodes are provided for three phase electrical supply.

In accordance with another embodiment of the invention the electrodes are in a form of discs describing an arc of a circle and the wiper blades reciprocate angularly over the electrodes, in a motion much like a motor car windscreen wiper. This could be provided in a humidifier having the further characteristics described above with reference to the continuously rotating wiper blades.

THE DRAWINGS

The invention is more fully described byway of example with reference to the drawings, in which:—

FIG. 1 is an isometric view of the humidifier in simplified illustration,

FIG. 2 is an end view of the humidifier steam generating tank,

FIG. 3 is a cross-sectional view of the tank,

FIG. 4 is a plan view of the top lid of the tank,

FIG. 5 is a cross sectional view of the lid,

FIG. 6 is a plan view on the lid,

FIG. 7 is a series of views in orthogonal projection of the bracket,

FIG. 8 is a series of views showing the motor shaft and clip,

FIG. 9 is a series of views of the shaft bearing bracket,

FIG. 10 is an isometric “exploded” view of a humidifier bottle,

FIG. 11 is a plan view of the humidifier bottle electrodes and wipers.

THE PREFERRED EMBODIMENT

As shown in FIG. 1, the electrode humidifier 1 has four electrodes 2, 3, 4 and 5, which are engaged by wiper blades 6, 7 and 8, which are continuously rotated during steam production. The wiper blades are mounted for this purpose on a shaft 9 which is turned by a motor 10. The tank has an outlet 11 for steam, an inlet 12 for water and a drain 13. The electrodes are connected to a three phase supply at connection points 14, 15, 16 and 17, points 14 and 17 connected to phase #1, point 15 to phase #2 and point 16 to phase #3.

Having the electrodes stationary and the wiper means rotated simplifies the electrical connections to the electrodes as shown, the steam tank contains the water for production of steam and the water level 18 controlled, for example kept above the water inlet and below the shaft. A triac can be used to vary the voltage applied to the electrodes, the water level may be kept constant and may be a lot higher than shown in this example.

The wiper blades are made of selected material, for example silicon rubber, which endures the temperature in the tank and wipe the deposits continuously off the electrodes, which may be made of stainless steel, for example.

The humidifier has a rectangular tank having a base 19, sides 20, 21, 22 and 23 and a roof or lid 24, with the electrodes depending from the roof of the tank. The horizontal shaft extends across the tank carrying the wiper blades, the shaft passing through a sealed hole 25 that incorporates seals in the tank wall at one end to be driven by the suitably geared electric motor, the other end of the shaft may be journalled in a bracket inside the tank (not shown). The boiler tank can be made of transparent material, for example at least the roof of the tank is made with transparent material, e.g. polycarbonate to allow observing the operation and conditions in the humidifier.

These are the main features of the humidifier, shown in this simplified isometric drawing, it will be apparent to those skilled in this art that various dimensional and other modifications can be made within the scope of the invention.

FIGS. 2 to 9 show various components of a particular design for implementing the invention, as a guide the same reference numerals are used as were used in FIG. 1 to indicate the corresponding parts. In FIG. 4 slots and holes 26, 27, 28 and 29 are indicated for the electrodes and connection points 2, 3, 4 and 5 and 14, 15, 16 and 17 respectively.

As shown in FIGS. 10 and 11, the electrode humidifier bottle 30 has three electrodes 31, 32 and 33, which are engaged by wipers 34, 35 and 36, which are continuously reciprocated linearly during steam production. The wipers are mounted for this purpose on a shaft 37 which is reciprocated by a linear actuator (not shown).

The tank has an outlet for steam, an inlet for water and a drain and other connections. The electrodes are connected to a three phase supply.

Having the electrodes stationary and the wiper means oscillated simplifies the electrical connections to the electrodes, the steam tank contains the water for production of steam.

The wiper blades are made of selected material, for example silicon rubber or a rather more abrasive material, which endures the temperature in the tank and wipes the deposits continuously off the electrodes, which may be made of stainless steel, for example.

REFERENCE NUMERALS

-   1 HUMIDIFIER -   2 ELECTRODE -   3 ELECTRODE -   4 ELECTRODE -   5 ELECTRODE -   6 WIPER BLADE -   7 WIPER BLADE -   8 WIPER BLADE -   9 SHAFT -   10 GEARED ELECTRIC MOTOR -   11 STEAM OUTLET -   12 WATER INLET -   13 DRAIN -   14 CONNECTION POINT -   15 CONNECTION POINT -   16 CONNECTION POINT -   17 CONNECTION POINT -   18 WATER LEVEL IN USE -   19 BASE -   20 SIDE WALL -   21 SIDE WALL -   22 SIDE WALL -   23 SIDE WALL -   24 LID -   25 HOLE FOR SHAFT -   26 SLOT AND HOLE -   27 SLOT AND HOLE -   28 SLOT AND HOLE -   29 SLOT AND HOLE -   30 HUMIDIFIER -   31 ELECTRODE -   32 ELECTRODE -   33 ELECTRODE -   34 WIPER -   35 WIPER -   36 WIPER -   37 SHAFT 

1. An electrode humidifier characterized in that the electrodes are engaged by wiper means and a relative motion between the electrodes and the wiper means is continuously or continually applied during operation of the humidifier, and in which the wiper means, in the form of blades, are moved in a rotational movement, mounted on a shaft which is driven rotationally.
 2. An electrode humidifier as claimed in claim 1, in which the electrodes are stationary and the wiper means is moved, with electrical connections provided to the electrodes which are located in the steam tank in which water is contained for production of steam.
 3. An electrode humidifier as claimed in claim 1, in which the wiper means operates also on other scale collecting surfaces.
 4. (canceled)
 5. An electrode humidifier as claimed in claim 1, in which the electrodes are in a form of a circular disc dimensioned so that the wiper blades move rotationally over the whole electrode surface.
 6. An electrode humidifier as claimed in claim 1, which includes a rectangular tank with electrodes depending from the roof of the tank, a horizontal shaft extending across the tank and carrying wiper blades arranged to wipe the operative surfaces of the electrodes, the shaft passing through the tank wall at one end to be driven by a suitably geared electric motor.
 7. An electrode humidifier as claimed in claim 1, which is made with provision of four electrodes and adapted to be powered as a single phase device or a three phase device by arranging the electrical connections to the electrodes accordingly.
 8. (canceled)
 9. An electrode humidifier as claimed in claim 1, which is applied to a steamer bottle which has a generally hollow upright cylindrical shape with linear electrodes depending from the top of the bottle.
 10. (canceled)
 11. An electrode humidifier as claimed in claim 1, which includes a rectangular tank with electrodes depending from the roof of the tank, a horizontal shaft extending across the tank and carrying wiper blades arranged to wipe the operative surfaces of the electrodes, the shaft passing through the tank wall at one end to be driven by a suitably geared electric motor.
 12. (canceled)
 13. (canceled) 